1. Field of the Invention
The present invention relates to a variable magnification lens system, and more specifically relates to a variable magnification lens system for use in copying machines for copying at 0.5-2 magnification.
2. Description of the Related Art
Conventional variable magnification lens systems are known to comprise a positive first lens unit and a negative second lens unit.
Conventional variable magnification lens systems, however, cannot adequately correct curvature of field and off-axial astigmatism, and therefore cannot achieve a wide angle with a few lens elements. Furthermore, conventional constructions make it difficult to provide the copy machine in compact form.